Safety device



2 Sheets-Sheet l ENTOR Jan. 10, 1950 1 WILLIAMS ETAL SAFETY DEVICE FiledJuly 30, 1945 Jan. 10, 1950 L. WILLIAMS ET AL SAFETY DEVICE 2Sheets-Sheet 2 Filed July 50, 1945 THF/l Patented Jan. 10, 1950 UNI TEDf vICE 2.494.438 "SAFETY DEVICE Lmvrenmeg` Williams fand Edward J.VVusler, Daye- .-ton,hio, assignorsztp .('icmn'alMotorsCorpora.,4 tion,Detroit,Mich-., a. corporationeofrDelaware.

Applicationzlyf, 1945; SerialiNog 6075720 4:01am. (CLM-55)'Ihiszinyentionxrelatesito ing machine;v

It is among thenobjects ofthe present invention to provide la.processing machinewifth'asaety an improved processdevice "which prevents.Y .certainportions4 thereof.;

:supported by -a powerfdevice:idurlngs'operation of the machine, .fromdroppingvdu'eto grav-ity. when said power device is renderedVineffective vWhile thema-chine is notaitilized.

Further objects-and advantages offfthe present a invention will beapparent vfromthe following-de- `fscription, reference 'fbeinghadto-fthe accompanying dra-Wings .Whereina preferred embodimentfof thepresent .invention is @clearly Vshown;A

The .Inacliinal asi shown .in the present ydraw;-l

ings comprises a frame having-a vcanrier --slidabli7 .attachedtheret'saidcarrier supporting z.tlfxe 'processing tool and itsoperator..A prime mover,-.in the form ofan electric incitarn is ycarried by `-theframe and; drivesa -cam.-,. .A lil-uid powenactuated .revolution of thecam out ofits frestpositiomthe:

carrier will be moved bythe cam in `one direction against thecounteractingforce of the fluid power actuated .dev-ice andduring-another'portion .sa-id carrier .iwi-ll` be moved in..the-opposite direction by the'fluid power actuated-device.' -un- 1der. the con-trol of the cam. f rvIll'xe.safetydevice, which preventsthe :carrier-y irom lfaillingdue:to gravity and particularly When-theuid poweractuated device .is deenergized,A provided by a block or .lugonthe cam, which is vinthe path `of r.

movement of the carrier cam `follower. when .the cam :is .in.its-restpostion and which is-moved .out vof this path uponfrotationofk'the cam.

In the drawings:

Fig. V1 showstheprocessingmachine in side :i

elevation.

Fig. .2 is a lplan view ci the machine. Fig. 3 is a. fragmentarysectionalfvie'wpartly in; section, showing certain" ofthe operating de#"tails' of "the" machine: t

Fig. 4 is a detail View of thelcontrolrswitchfac' tuator. l

Fig. I5 is al diagrammaticview'showingfthe'contour ofthe workingsurfaces'of 'thezcami Referring to the drawings thea-machine sis;

shownl comprising :a iframe .2 f+ :having t vertical slide-ways or gibs2| to which the carrier..2z-fis .su-dany; attached.- .rrmsfcamersghasf@Hangul ar platform.' '.2 upon .which thezrzel'ectric .motorini-:isa

bythe: motor 241; 4drivesav shaft which in iturn operates'theprocessing. tool, a drill or the like, not shown in-fthe:drawings:A Whena cutter, broach orzaiiyrtype Vof :reciprocating .tool is'tobe yused:withth-e machine, then the motor 2d lis, eliminatedandsanyrsuitable.toolholderf is attached to the platform 23.

Carrier 22 has an opening 26a in which a block Z55-maybe secured :in`vertically adjustable Aposintionsmntthe .carrierfby .thepnch'plate271.v An

abutment .28 is. provided :on :block A2li, said .v abutment `vl.lyingfsubstantiallyssin thezplanezof the gibs `or:slide-Way 2l l A-camffollower stud i29 is .journailed.intbearings;provided in block 25one .end

noia -the'cam'follower extending. from :said block.

Whenfthe" block-261is .in lits normal rest positionand.likewisexthemarrier 22.,y Afor one is secured to themtherxfsothatnboth move together, said block engages the one. endl vofna .rod 3l,slidably sup- ;fportediinthe .frame 20, the 4other end of ksaid ,rod

engaging .a resilient bumperyelernent 32 .supported inwthesrecess ofthe. housing.A

.Aqprimefmover or. electric motor t is carried .by v.fra-Ine Mean-dnas a:shaft 4 l extending into a A:compartment .formed by two 'reinforcingWalls 42 andy I3-inthe trarne. This shaft .has a Worm ,pin-

ion 4t2-securedu thereto :which .meshes with and drives the wormwhee145. A shaft 4@ journalled .inbearingslf and 48-carried byvwallsl2and 43 Irespectively...has the `worm wheel y secured .thereto and alsoya :pinion 49.

This pinion 49 meshes'with .andndrives-.gear 50 splined to shaftilfwhich is jour-nalledfin twobearings 52 and 53 carried respectivelybythe `vvalls 42 .and 43. The

fgendxofshaft 5l'feXtendir1g beyond bearing 53 has anfanchor plate-'ordisci-54 .secured thereto, tov

-whichfthezcam .55is bolted. .The working, .pe- .ripheral surface -56ofthe. cam is 'engaged by the .camffollotver ZiQtandzthe carrier. Thecontourof .the workingsurfa'ceof cam `55 .is shown by Fig. 5.

The-.means :For urging'zthe'carrier ,so that `the cam follower-Sthereonis-.maintai-nedin con- '.'stant-.engagement with-.the working `surface56 `of tl'zcam..55comprises fa -uid pressure device-5) l .andrailei/'enti :actuated thereby. To compensate .fof .varyng' weight .of the:carrier and. its ,equipvrment.it,sometimesgis.necessary 4to change theone ofQthese/holes maybe inserted/a bolt Whichis I threadedlyreceitedbyaanyfone. .ofthe threeholes tween the radial lines c and ydfis agentle rise pushing the cam follower against the countervacting force ofdescribed.

3 shown in Fig. 1, the pivotal bolt which attaches the lever to theframe extends through the hole 63 in the lever and is threaded into thehole 66 of the frame. This makes the oppositely disposed portions of thelever substantially equal.

The fluid pressure device 60 comprises a cylinder l removably attachedto the cover ll of the frame, in which cylinder there is provided apiston having a rod l2 which extends outside the cylinder 'IU andswivelly engages a recessed end of lever 5l. the abutment 28 of block2B, substantially in the plane of the gibs or slideway upon which thecarrier 22 attached to block 2B, maybe reciprocated. When the device 69is energized, that is, when fluid under pressure is introduced into theThe other end of said lever engages cylinder l0, the piston and its rod'l2are urgedy ,supported thereby. Thus the cam follower 29 on thecarrier is constantly urged into contact with the working surface of thecam 55 by the lever 6l. l

The Fig. 5 shows the contour of the cam in its normal rest position inwhich the fcam follower v29 assumes the positions H. ,In this positionthe lug 80, formed integral with or secured to the cam, lies directly inthe path of movement of 'the cam follower 29 and thus, if the fluidpressure device 69 is deenergized at this time and: therefore eliminatesthe supporting function of the lever 6 l, the carrier and its attachedelements will be prevented from dropping inasmuch as the cam follower 29on the carrier will engage with and be supported by this lug. As thecam' n55 is rotated clockwise (Fig. 5) the cam follower 29 rides overthe cam surface 56a to the point where the radial line a intersects thecam surface 5f during which time and in response to such movement of thecam follower, carrieris quickly moved downwardly a predetermineddistance away from its normal rest position and toward the workpiece tobe processed, The cam surface 56h, extending from the radial line a tothe radial line b progressively moves away from the center of the cam sothat, as the cam follower traverses this portion of the cam surface thecarrier is moved gradually toward the workpiece to .be processed, at adefinite rate and for a predetermined distance. As soon as the cam.follower passes the plane of the radial line b, it will roll along thecam surface 56e which is an abrupt step-olf toward the center of thecam. Now the fluid pressure device acting through the lever Sl, movesthe carrier and its accoutrements upwardly toward its normal restposition, this quick return of the carrier terminating when the camfollower reaches 4the cam surface 56d at the radial line c. The camsurface IElid bethe lever 6| for purposes to be The end of shaft 5lextending beyondthe gear r5G is splined to receive the lever 85 lwhichmay be placed upon the shaft in one of several positions rotatably, tovary its angular relation relalever 8B and concentric with shaft 5|receives a clamping bolt 88 the headed end of which extends through anopening in lever 85. Thus lever 86 is rotatably adjustable relatively toshaft 5| and may be secured in such adjusted position by clamping it tolever which is splined to shaft 5l. Lever 8B, when rotating ',withshaftl engages the rod 89 to open the limit switch 90 and thus break thelcircuit through the holding coil (not shown) of the circuit controller94 thereby causing said controller to break Athe .circuit to the primemover or electric motor 40 and stop its operation. A button 95 on the'controller 94, when pressed closes the circuit vswitch Si] is securedto the frame cover 'Il in any V'suitable mannersothat'its actuator rodor member 89 may be engaged bythe lever 86 and moved thereby. The limitswitch is opened to stop the operation of the motor 40 when the camfollower 129 substantially reaches the position on the cam in the planeof the radial line b so that as the motor coasts to a full stop afterbeing deenergized by the breaking of its circuit, said cam follower 29willvride down the cam surface 55C `underthe effect of the fluidpressure device and its lever 5l. When reaching the position in theplane of radial line c (Fig. 5) the cam follower rides on the camsurface 56d which, as has been lmentioned-is of gentle rise, thus thecam follower 29, in moving to the position H, is moved Aoutwardlyagainst the force of the lever 6l. This cam follower movement occurswhile the deenergize'd motor 40 is coasting to a stop, the counteractingforces all effecting a braking effort upon the motor which assures a'full stop thereof sometime while the cam follower is riding the camsurface 56d. Now, as has been described. the lug 88 isdirectly in thepath of movement of the cam follower 29 thereby providing a supportwhich is engaged by and which prevents dropping of the heavy carrier andits accoutrements in the event the fluid pressure de- 'vice isdeenergized and does no longer provide the supporting force exerted uponthe carrier 22 through the lever 6 l.

The type of cam used in the present invention that is, a cam whose outerperipheral surface is the working surface, offers the minimum ofresistance and friction and thereby permits the use to easy sliding andeliminates tilting which would increase friction. .This also contributesto the use of a comparatively smaller motor for actuating the carrier.

By adjusting the pivotal connectionvof lever 6l to frame 20 a variableleverage may be obtained substantially to maintain the preferred ratiobetween theforce exerted by the fluid pressure 'device and the weight ofthe carrier and its equipment. L

In order to obtain different speeds of the proc- 'fessing tool,especially a' vdrill'or similar device H rotated bytheshaft 26, the,operator may replace one train of speed reducing gearing '25 withanother suitable for the requirements. To change the feed speed, thegearing between the motor 40 and the cam driving shaft 5I may bealtered. Various types of cams 55 may be secured to the shaft 5| to suitang7 condition. The machine is designed to make the said gearing easilyaccessible and changeable.

The interior of the frame 20 is suitably reinforced with ribs towithstand stresses and eliminate fractures when the machine is used forheavy duty work. The frame has a base portion |00 which is adapted to besecured to any desired foundation and especially to the well knownrotatable indexing table upon which a plurality of these machines may bemounted each to do a speoic processing job at a particular station inthe rotating path of the table.

While the embodiments of the present invention as herein disclosed,constitute a preferred form, it is to be understood that other formsmight be adopted, all coming within the scope of the claims whichfollow.

What is claimed is as follows:

1. A safety device for apparatus consisting of a reciprocative carrierheld in operative engagement with the outer contour of a rotating cam bya power actuated lever whereby said carrier is moved in one direction bysaid lever, under the control of the rotating cam and moved in theopposite direction by the cam itself against the effect of said poweractuated lever; and a detent operatively connected to the cam and heldthereby in the path of carrier movement while said cam is in normal restposition, whereby automatic movement of said carrier is prevented whensaid lever is rendered inoperative while the cam is in normal restposition.

2. A safety device for a vertically reciprocative carrier comprising incombination, a rotatable cam; a pivoted lever; power means operative tomove the lever into engagement with the carrier and urge said carrierinto operative engagement with the cam whereby movement of the campermits movement of the carrier by said lever in one direction andmovement of the carrier by the cam in the other direction; and asupporting block on the cam and maintained in the path of carriermovement when said cam is in normal rest position, said block preventingdropping of the carrier when the power means is rendered inoperativewhile the cam is at rest.

3. A safety device for a vertically reciprocative carrier comprising incombination, means operative positively to actuate said carrier in bothdirections said means consisting of a rotatable cam and a power actuatedlever urged into constant engagement with the lower side of the carrier,the cam actuating the carrier downwardly against the effect of saidpower energized lever and the lever actuating said carrier` upwardlyagainst the cam; and a detent movable by said cam into the path ofcarrier movement and maintained in said position while said cam is innormal rest position, whereby dropping of the carrier due todeenergization of the lever while the cam is in the rest position isprevented.

4. A safety device for a vertically reciprocative carrier comprising incombination, means operative positively to actuate the carrier in bothdirections said means comprising a rotatable cam and. a lever yieldablyurged to engage the carrier and lift it into operative engagement withthe cam; means operative, when energized, for urging the lever to liftthe carrier; and a detent integral with the cam and moved into the pathof carrier movement during a portion of a revolution of said cam, saiddetent preventing automatic downward movement of the carrier while thecam is in this position and the lifting effect of the lever isdiscontinued by rendering its energizing means ineffective.

LAWRENCE WILLIAMS. EDWARD J. VOSLER..

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date '128,226 Hargroves May 19, 19031,850,299 Watson Mar. 22, 1932 1,950,597 Corwin Mar. 13, 1934 1,951,093Johnston Mar. 13, 1934 2,054,018 Gilchrist Sept. 8, 1936 2,114,013 BallApr. 12, 1938 2,391,702 Hill Dec. 25, 1945

